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151.
因变更了初期坝轴线,Ⅲ号冲沟斜坡在清基中发现了隐蔽发育于中厚层白云岩中的卸荷裂隙,裂隙宽度0.10~1.00m,深度3.20~4.50m。根据勘探及试验资料,进行了斜坡稳定性和渗透性评价。结论得出:(1)在天然状态下,K>1,斜坡稳定;(2)在饱水状态下,沿m2滑移结构面,K<1,斜坡不稳定;(3)斜坡浅层管道式渗透作用,将产生渗透破坏。建议采用团结——帷幕溉浆作防渗处理。 相似文献
152.
本文通过对试验机-试样系统的分析,认为试验的稳定加载条件不仅仅取决于试验机和试样的刚度(K_m+K_r),而且取决于试验机活塞(端部)的位移速率.具有反馈系统的伺服试验机,正是通过对活塞位移U_q的控制来谐调刚度(K_m+K_r)的变化,从而达到控制应变速率,以保证加载过程的稳定. 相似文献
153.
Weixuan Fang Ruizhong Hu Wenchao Su Jiafei Xiao Liang Qi Guohao Jiang 《科学通报(英文版)》2002,47(10):874-880
Emplacement ages of lamproites that comprise lamproite and olivine lamproite in Zhenyuan County, Guizhou Province, China, have been constrained by the whole-rock Sm-Nd and Rb-Sr isochron methods and the whole rock K-Ar method. Intrusive activities of lamproites in the Sinantang area of Zhenyuan County, Guizhou Province, took place during the Late Cambrian, as indicated by the Sm-Nd isochron ages ( t ) = (503 ± 17) (2σ) Ma and by the Rb-Sr isochron ages ( t ) = (501.2 ± 4.6) (2σ) Ma. Intrusive activities of olivine lamproites at the Maping with Ⅱ-type diamond and Xitou in Zhenyuan County, Guizhou Province, took place from the Late Cambrian to the Early Ordovician, as evidenced by the Sm-Nd isochron ages ( t ) = (502 ± 27) (2σ) Ma and by the Rb-Sr isochron age ( t ) = (502 ± 27) (2σ) Ma. This suggests that the upwelling hot materials derived from the deep mantle were emplaced from the Late Cambrian to the Early Ordovician (503-497 Ma), while the time terminal of cooling of the geothermal event of magmatism-tectonism probably was at 442.64-435.54 Ma, as dated by the whole rock K-Ar method. 相似文献
154.
目的 评价禹城洼陷的生烃潜力,以指导下一步勘探。方法利用烃源岩分析数据对禹城洼陷的生烃潜力进行研究和评价,利用包裹体测温等分析资料对影响烃源岩发育和分布的因素进行分析和总结,利用生物标志化合物指标(C29S/S+R)对生油门限进行了重新认识和探讨。结果禹城洼陷烃源岩发育较差、分布不均,总体上处于未熟一低熟阶段;其主要影响因素是异常高压带的分布和火成岩的入侵;本区生油门限应在3500m以下。结论禹城洼陷下第三系生烃潜力不足。 相似文献
155.
Thehydraulicfracturingtechniqueiswidelyused intheoilengineering,naturalgasexploiting,under groundheatextractingandothermineralresources mining,etc.withwelldevelopedhydraulicfracture modelsforordinaryrocks[1—3].Inthefieldofsolu tionminingofsaltdeposit,thistechniqueisusedto producefracturealongtheplanelayerofthedeposit,thustoconnecttheinjectionandtargetwells[4,5].However,duetothespecialphysicalandmechanical characteristicsofrocksalt,executinghydraulicfrac tureinrocksaltdepositisdifferentfromtha… 相似文献
156.
低渗透岩石非饱和非Darcy渗流机理 总被引:4,自引:0,他引:4
为了探讨低渗透岩石非饱和非D arcy的机理,以毛管模型为基础,通过对流体非饱和系列流动状况的运动分析,相应推导得出流体非饱和渗流的毛管模型,从理论上论证在微小尺度孔隙中流体自身的力学特性,以及与固体、气体的相互作用,指出毛管压力与边界层的存在,是导致流体非D arcy渗流现象的一个主要原因。研究这些因素对渗流运动的影响机制,是探索低渗透岩石非D arcy渗流机理的一个重要方向。 相似文献
157.
High-quality hydrocarbon source rock in the Paleogene sequence of the Ping Chau Formation, Hong Kong
YAOSuping HUWenxuan CHENLongsheng ZHUDongya XUEChunyan 《科学通报(英文版)》2005,50(2):145-154
Although petroleum exploration is being conducted in the Hong Kong region, high-quality hydrocarbon source rocks have never been found in this area. The Ping Chau Formation is only Mesozoic-Cenozoic sedimentary rock exposed in Hong Kong and its surrounding areas. The hydrocarbon source rock of the Ping Chau Formation is very rich in organic matters, which has an average total organic carbon (TOC) of 1.9% and chloroform bitumen ““A““ range from 0.14% to 0.24%. The total hydrocarbon content varies from 880 to 1800 ppm and the transformation ratio is specific from 5 to 9. The index of pyrolytic hydrogen is up to about 600 mgHC/gTOC. These data demonstrate the characteristics of the high-quality hydrocarbon source rock. The lamalginite is the major maceral of the source rock of the Ping Chau Formation, and geochemical characteristics also suggest that the organic materials of the source rock are of type I and type Ⅱ1, with abundant gammacerane, γ, β-caro-tane and C24 tetracyclic terpane, which indicate that it was formed in the salt water and brackish water sedimentary environment, and the source rock has evolved into a mature phase. The organic inclusions are found within calcite veins in cracks of the source rock, indicating that hydrocarbon has been generated and a secondary migration has happened. The source rock in the Ping Chau Formation is about 200-300 m thick, thus having considerable hydrocarbon potential. The discovery of the high quality hydrocarbon source rock in the Ping Chau Formation will certainly provide insight on hydrocarbon resource exploration in the South China Sea area. 相似文献
158.
A large number of pneumatic rock drills are being extensively used in a majority of mines in China nowadays, with a high noise level up to 125 dB(A) and large vibration and oil-fog on working-site, which can seriously jeopardize manipulator' s body and mind. Aiming at improving drilling environment and labor safety condition, the production mechanism of noise of all sorts of rock drills including pneumatic hydraulic and water-powered rock drills and measures of reducing noise level of pneumatic rock drills in special were discussed and led to the conclusion of that the pneumatic rock drills should be eliminated step by step, the hydraulic rock drill should be developed at full speed and especially the water-powered rock drill should be studied and applied according to the situation of China. In addition, the reasons of why hydraulic rock drills have not yet been used extensively and spread wide areas in China were discussed. The main technical parameters of newly developed leg-supporting water-powered rock drill and the comparation of experimental data between pneumatic rock drill and hydraulic rock drill were listed. The experimental results show that water-powered rock drill possesses the same superior properties as hydraulic rock drill and its noise is less than 20 dB(A) than pneumatic rock drill and there is no oil-fog on the working-site and vibration is reduced largely~ but its drilling speed is raised largely , its structure is simpler, and maintenance is convenient. Therefore, popularizing applying of water-powered rock drill will be an effective way of improving mine working environment according to the current situation of China. 相似文献
159.
张永利 《辽宁工程技术大学学报(自然科学版)》2006,25(6):836-838
描述了岩石材料在磨料射流的冲击下破坏的主要原因,分析了应力波就是岩石局部受到拉伸和剪切井最终使岩石发生破坏的根本因素,在这一假设的前提下采用波动理论建立了岩石受应力波作用的力学模型即射流波动的基本方程,在已知的边界条件下推导出了由波动引起的最大正应力的计算公式。通过该公式对具体实例进行了理论计算,并把该计算结果与在河南油田所进行的地面磨料射流割缝的现场实验结果进行了比较,证明两种结果吻合的较好.说明这种理论分析方法是可行的。 相似文献
160.
潍北凹陷孔店组烃源岩生物标志物特征及地球化学意义 总被引:6,自引:1,他引:6
通过对潍北凹陷孔店组烃源岩有机质丰度、类型、成熟度及生物标志物的研究,发现孔店组烃源岩重排甾烷含量低,C27,C28和C29规则甾烷含量较多,C29甾烷的20S/(S R)和C29ββ/(ββ αα)比值分别在0.12~0.38和0.3~0.45之间;在萜类化合物中,奥利烷含量低,γ蜡烷与C30藿烷比值在0.1~0.37之间.研究结果表明孔店组烃源岩生源以高等植物为主,混有一定比例的藻类等低等水生生物,沉积环境为含盐度低的弱还原-弱氧化湖沼相,烃源岩有机质处于低熟-成熟阶段. 相似文献